This time, the United School Employees of Pasco has filed a charge with the Florida Public Employees Relations Commission. The complaint comes a year after it settled a class-action grievance over workload concerns.

She observed that the district has required teachers to attend "professional learning community," or PLC, meetings lasting more than 40 minutes weekly, and alleged that the sessions go beyond contractual agreements.

The contract states, "Weekly professional development will be designed for all teachers to meet the needs of their students. Weekly professional development may vary in length but should not be required to exceed 40 minutes."

Webb said the PLC meetings are not planning, because of the nature of the things that teachers are required to do there, such as analyze academic standards and create grading scales.

Superintendent Kurt Browning disagreed that the strategy violates the contract.

After taking office in late 2012, Browning established professional learning communities to allow teachers to collaborate. It's not training or development, he said.

"It is planning — deliberate planning time, group planning," Browning said. "Perish the thought that we would have teachers talking to each other about instruction, instructional practices and students at this time, as opposed to teaching in isolation."

Assistant superintendent Amelia Larson has portrayed this model as more than simple meetings. Sometimes, she's referred to it as a "way of life."

Larson commented about the PLC system on Twitter shortly after the union filed its complaint.

"PLCs empower schools to create the kind of thoughtful and intentional communities that both students and teachers deserve!" she wrote.

To the USEP, though, they represent another meeting that takes away from preparing instruction.

Similar issues led to the union's 2012 grievance, which Browning settled by reducing district-required tests and telling principals to scale back staff meetings. Executive director for administration Kevin Shibley reiterated the need to protect planning time in a memo regarding a March teacher planning day.

Shibley cited the contract as he reminded principals not to schedule mandatory PLCs and to avoid faculty meetings that day.

Browning said he took steps that his predecessor did not to alleviate demands on teachers. "It's better today than when I took office."

He acknowledged that the system is not perfect. But he said he had heard from teachers and principals who appreciate the new way of doing things and seen positive outcomes in the classroom.

Webb said teachers she had spoken to held a very different point of view. The loudest complaints came from elementary schools.

Talks to resolve the issues did not help. So the USEP turned to the state.

"They can't unilaterally change 30 years of operating without having to collectively bargain it," Webb said. "They say they want the union to work with them, yet when the union brings these objections, they're not willing to make accommodations."

The case could lead to a state ruling, or the sides could negotiate a deal before that happens.